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The Asian – East African Flyway is a group of well-established routes by which many species of birds migrate annually between mid-Palearctic breeding grounds in Asia and non-breeding sites in eastern and southern Africa. ==Route== The flyway covers an area of and spans 64 countries from South Africa and Madagascar to Eastern Siberia and Alaska. The indirect route, where the birds fly west and then south rather than directly south, avoids the obstacle of the Tibetan Plateau and the Himalayas. The birds usually migrate quickly from the Palaeartic to northeast Africa, reaching Ethiopia or Northern Sudan by late August or September. Some birds then remain in northern Africa for most of the fall before heading south either via Uganda and the Lake Victoria basin or via the Kenyan highlands. In the spring, many birds complete the return journey in six weeks or less, usually taking a route along the coast of East Africa. 331 species use the flyway. Seven sites along the route have over a million birds. About 25 species come from the far eastern Paleartic or even from Alaska. These include the northern wheatear, willow warbler and barn swallow. The willow warbler is the most numerous of the birds migrating along this route, accounting for 15.8% of the total number of passerines and near-passerines. Raptors such as the steppe buzzard also migrate along the flyway in large numbers. Some species follow variants of the route. The Amur falcon breeds in northeastern Asia and overwinters in southern Africa, making a round-trip journey of . Most of these birds fly south along the eastern edge of the Tibetan Plateau and stop in northeastern India and Bangladesh for several months. In late November the falcons cross India and fly in great flocks over the Indian Ocean to Somalia and Kenya. They return via the Arabian peninsula, Iran, Afghanistan and Pakistan. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Asian–East African Flyway」の詳細全文を読む スポンサード リンク
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